| McCollum, Gregory D. Mr Sr. | President | US | UN | 1 |
| McCollum, John | U.S. House | SC | Republican | 1 |
| McColumn, Jonathan Mr | U.S. Senate | GA | Republican | 1 |
| McConkey, Josh | U.S. House | NC | Republican | 1 |
| McConnell, Jonathan Edward | U.S. Senate | AL | Republican | 1 |
| McConnell, Mindy | U.S. House | LA | Libertarian | 1 |
| McConnell, Mitch | U.S. Senate | KY | Republican | 6 |
| McCorkle, Isaac Ian | U.S. House | CO | Democratic | 1 |
| McCorkle, William | U.S. House | SC | Republican | 1 |
| McCormack, Holly | U.S. House | GA | Democratic | 2 |
| McCormick, Dave | U.S. Senate | PA | Republican | 3 |
| McCormick, Karen A Dvm | U.S. House | CO | Democratic | 1 |
| McCormick, Ray | U.S. House | IN | Democratic | 1 |
| McCormick, Richard Dean Dr. | U.S. House | GA | Republican | 2 |
| McCorriston, Byron Mr | U.S. House | HI | NON | 1 |
| McCotter, Thaddeus G | President | US | Republican | 1 |
| McCoy, Lisa | U.S. House | GA | Republican | 1 |
| McCracken, Tricia | U.S. Senate | GA | Democratic | 1 |
| McCrackin, Curtis M | U.S. House | CO | Republican | 1 |
| McCray, Valerie L Dr | U.S. Senate | IN | Democratic | 1 |
| McCray, Valerie Lin Dr. | President | US | Independent | 1 |
| McCready, Daniel | U.S. House | NC | Democratic | 1 |
| McCrory, Patrick Lloyd | U.S. Senate | NC | Republican | 1 |
| McCutcheon, Shaun | President | US | Libertarian | 1 |
| McDade, Clair Marie | U.S. House | VA | Republican | 1 |
| McDaniel, Christopher Brian | U.S. Senate | MS | Republican | 1 |
| McDaniel, Joseph Stewart II | U.S. House | TX | Republican | 1 |
| McDermott, James | U.S. House | WA | Democratic | 1 |
| McDermott, Robert C | U.S. Senate | HI | Republican | 1 |
| McDermott, Thomas M Jr | U.S. House | IN | Democratic | 1 |
| McDermott, Thomas M. Jr | U.S. Senate | IN | Democratic | 1 |
| McDevitt, David Malcolm Mr | U.S. House | WA | Democratic | 1 |
| McDonald, Darlene | U.S. House | UT | Democratic | 1 |
| McDonald, Mark | U.S. House | NM | Democratic | 1 |
| McDonald Rivet, Kristen | U.S. House | MI | Democratic | 1 |
| McDonald Trani, Annette | U.S. House | CA | Democratic | 1 |
| McDonough, Melissa A | U.S. House | TX | Democratic | 1 |
| McDougal, Ryan | President | US | NNE | 1 |
| McDow, Daniel | U.S. House | FL | Democratic | 1 |
| McDowell, Addison | U.S. House | NC | Republican | 1 |
| McDowell, Alyssa Dara | U.S. House | KY | Republican | 1 |
| McDowell, Aquasia Johnson | U.S. House | FL | Democratic | 1 |
| McDowell, Jan | U.S. House | TX | Democratic | 2 |
| McEachern, Deaglan | U.S. House | NH | Democratic | 1 |
| McEachin, Aston Donald | U.S. House | VA | Democratic | 1 |
| McFadden, Adam | U.S. House | NY | Democratic | 1 |
| McFadden, Melissa | U.S. House | SC | Republican | 1 |
| McFall, Jerald Steve | U.S. House | NM | Republican | 2 |
| McFarland, Jay Jaymac | U.S. House | UT | OTH | 2 |
| McFarlane, Walter James III | U.S. House | NH | Republican | 1 |
| McFarlin, Jeff | U.S. House | TX | Republican | 1 |
| McFeeters, Kenneth R | U.S. House | AL | Republican | 1 |
| McGannon, James | U.S. House | CO | Democratic | 1 |
| McGarvey, Morgan | U.S. House | KY | Democratic | 1 |
| McGee, Brian James | U.S. Senate | AL | Democratic | 1 |
| McGee-Smith Kearney, Vanessa | President | US | Independent | 1 |
| McGill, Michael | U.S. House | MS | Republican | 1 |
| McGinley, Mark J | U.S. House | MT | Republican | 1 |
| McGinn, Randi | U.S. House | NM | Democratic | 1 |
| McGinty, John | U.S. House | PA | Democratic | 1 |
| McGinty, Kathleen Alana | U.S. Senate | PA | Democratic | 2 |
| McGlover, John William | President | US | IDP | 1 |
| McGlowan, Angela | U.S. House | MS | Republican | 1 |
| McGonigal, Malgorzata | U.S. House | IL | Republican | 1 |
| McGonigal, Ryan James | U.S. House | CO | CON | 1 |
| McGovern, James P. Mr. | U.S. House | MA | Democratic | 1 |
| McGovern, Jay | U.S. House | FL | Democratic | 1 |
| McGovern, Kevin John | U.S. House | FL | Republican | 1 |
| McGowan, Angelynn Brooke | U.S. House | NC | Republican | 1 |
| McGowan, Jacqueline Marie | U.S. House | IL | Democratic | 1 |
| McGrath, Amy | U.S. Senate | KY | Democratic | 1 |
| McGrath, Amy | U.S. House | KY | Democratic | 1 |
| McGrath, Deb | U.S. House | WI | Democratic | 1 |
| McGrath, Thomas Pierce | U.S. House | CA | NPA | 1 |
| McGraw, Albert Douglas | U.S. House | PA | Republican | 1 |
| McGraw, Joe | U.S. House | IL | Republican | 1 |
| McGreevey, Jonathan A Dr | U.S. Senate | MD | Republican | 1 |
| McGuffin, James Dawson | President | US | Democratic | 1 |
| McGuigan, John David | U.S. Senate | PA | Democratic | 1 |
| McGuire, Barbara | U.S. House | AZ | Democratic | 1 |
| McGuire, Darrell | U.S. Senate | GA | W | 1 |
| McGuire, John | U.S. House | VA | Republican | 1 |
| McGuire, John J. Mr. III | U.S. House | VA | Republican | 1 |
| McGuire, Michael Mick | U.S. Senate | AZ | Republican | 1 |
| McGuire, Sean Thomas | President | US | Democratic | 1 |
| McGurn, Matthew James Mr | President | US | NNE | 1 |
| McHale, Judith Keenan | U.S. House | AZ | Democratic | 1 |
| McHenry, Patrick Timothy | U.S. House | NC | Republican | 1 |
| McHugh, Joe | President | US | Independent | 2 |
| McHugh, John H | U.S. House | PA | Independent | 1 |
| McHugh, John M | U.S. House | NY | Republican | 1 |
| McInnis, Charleta | President | US | Democratic | 1 |
| McIntosh, Angela E Ms | U.S. House | MI | Democratic | 1 |
| McIntosh, David Martin | U.S. House | IN | Republican | 1 |
| McIntosh, Elijah | U.S. House | OK | Democratic | 1 |
| McIver, Lamonica | U.S. House | NJ | Democratic | 1 |
| McKaughan, Daniel Cregg | U.S. House | TX | Republican | 1 |
| McKay, Raymond Tyler Mr | U.S. Senate | RI | Republican | 1 |
| McKee, Travis W | President | US | Republican | 1 |
| McKellar, Shirley Jonetta Dr | U.S. House | TX | Democratic | 1 |
| McKennon, Kerry Douglas | U.S. Senate | TX | Libertarian | 1 |
| McKenzie, Elizabeth Grace Ms | U.S. House | OH | UN | 1 |
| McKenzie, Jacob William Mr. | President | US | Republican | 1 |
| McKeon, Howard P "Buck" | U.S. House | CA | Republican | 1 |
| McKibben, Allen Harley II | U.S. House | MT | Republican | 1 |
| McKim, Ken | U.S. House | NC | Republican | 1 |
| McKinley, David B. Mr. | U.S. House | WV | Republican | 1 |
| McKinley, Douglas E. Jr. | U.S. House | WA | Democratic | 1 |
| McKinley, Michael Mr | President | US | Democratic | 1 |
| McKinney, Bryan | U.S. Senate | WV | Republican | 1 |
| McKinney, Dennis | U.S. House | KS | Democratic | 1 |
| McKinney, Javita | U.S. House | FL | Republican | 1 |
| McKnight, Quincy | U.S. House | TN | Republican | 1 |
| McLain, Kelly Mr. | President | US | Democratic | 1 |
| McLaughlin, Christy | U.S. House | FL | Republican | 1 |
| McLaughlin, Christy | U.S. House | FL | Republican | 1 |
| McLeay, Bartholomew L | U.S. Senate | NE | Republican | 1 |
| McLellan, Thomas Warren | U.S. House | VA | Democratic | 1 |
| McLendon, Floyd Jr. | U.S. House | TX | Republican | 1 |
| McLeod, Daniel Wright | U.S. House | GA | Republican | 1 |
| McLeod, Donna Theresa Ms. | U.S. House | GA | Democratic | 1 |
| McLeod, Elizabeth D | U.S. Senate | TN | Independent | 1 |
| McLeod, Jalen Dupree | U.S. House | CA | Democratic | 1 |
| McLeod-Skinner, Jamie | U.S. House | OR | Democratic | 3 |
| McLinko, Doug | U.S. House | PA | Republican | 1 |
| McMain, Marc | U.S. House | GA | Republican | 1 |
| McManus, Gary | U.S. House | FL | Democratic | 1 |
| McManus, Patrick | U.S. House | NY | OTH | 1 |
| McMillan, Jimmy (Aka) James | President | US | Republican | 2 |
| McMiller, Beniah | U.S. House | NC | Democratic | 1 |
| McMorris Rodgers, Cathy | U.S. House | WA | Republican | 2 |
| McMullen, John A | U.S. Senate | VT | Republican | 1 |
| McMullin, David Evan | U.S. Senate | UT | UN | 1 |
| McMullin, Evan / Mindy Finn | President | US | Independent | 1 |
| McMurray, Jennifer | President | US | Democratic | 1 |
| McMurray, Nathan | U.S. House | NY | Democratic | 1 |
| McMurray, Nathan Douglas | U.S. House | NY | Democratic | 1 |
| McMurtry, Todd | U.S. House | KY | Republican | 1 |
| McNeal, Justin Shad Mr | U.S. House | SD | Republican | 1 |
| McNeal, Justin Shad Mr | U.S. House | SD | Republican | 1 |
| McNeal, Wayne | U.S. House | MD | Democratic | 1 |
| McNeely, Linda | U.S. House | IL | Democratic | 1 |
| McNeil, Ana | U.S. House | ID | Democratic | 1 |
| McNeill, Frank | U.S. House | NC | Democratic | 1 |
| McNeill, Thomas G. | U.S. House | UT | OTH | 1 |
| McNeill, Thomas G. | U.S. House | UT | OTH | 1 |
| McNeil Sr, Andre Ramon | President | US | — | 2 |
| McNerney, Christopher Michael | U.S. House | TX | Democratic | 1 |
| McNerney, Gerald Mark | U.S. House | CA | Democratic | 1 |
| McNulty, Ellen Ej | U.S. House | MD | Republican | 1 |
| McNulty, Janet | U.S. Senate | WV | Republican | 1 |
| McPhail, Keith | U.S. House | TX | Democratic | 1 |
| McPhail, Sharon | U.S. House | MI | Democratic | 1 |
| McQuaid, John Dennis | U.S. House | CA | Republican | 1 |
| McQueen, Eldon Dan | U.S. Senate | MO | Republican | 1 |
| McQueen, Eldon Dan | U.S. House | TX | Republican | 1 |
| McQueen, Eldon Daniel | U.S. Senate | TX | IDP | 2 |
| McQuilken, Angus | U.S. House | MA | Democratic | 1 |
| McReynolds, Laurie Godfrey | U.S. House | TX | Republican | 1 |
| McSally, Martha | U.S. House | AZ | Republican | 2 |
| McSally, Martha | U.S. Senate | AZ | Republican | 6 |
| McStay, John Dr | U.S. House | TN | Democratic | 1 |
| McSweeney, David | U.S. House | IL | Republican | 2 |
| Meade, Matthew Allen | U.S. House | OH | Democratic | 1 |
| Meader, Cortland | U.S. House | NC | Republican | 1 |
| Meadows, Mark R | U.S. House | NC | Republican | 1 |
| Meadows, Samantha | U.S. House | OH | Democratic | 1 |
| Mealer, John Lewis | President | US | Independent | 1 |
| Medeiros, Adam Thomas Mr | U.S. House | CA | Republican | 1 |
| Medeiros, John Manimas Mr. | President | US | W | 1 |
| Medenbach, Kenneth | U.S. House | OR | Republican | 1 |
| Medina, Alexis | U.S. House | CA | Democratic | 1 |
| Medina, Ian Anthony | U.S. House | FL | Democratic | 1 |
| Medina, Ian Anthony | U.S. House | FL | NPA | 1 |
| Medina, Ian Anthony | U.S. House | FL | Republican | 2 |
| Medina, Ian Anthony | U.S. House | NY | Democratic | 1 |
| Medina, Ian Anthony | President | US | NPA | 1 |
| Medina, Ian Anthony Mr. | U.S. House | FL | Democratic | 1 |
| Medina, Ronald Razon Mr | U.S. House | TX | Independent | 1 |
| Medley, Stefan Paul Mr | U.S. House | TX | Independent | 1 |
| Meehan, Andrew | U.S. House | PA | Republican | 1 |
| Meehan, Patrick L. Mr | U.S. House | PA | Republican | 2 |
| Meehan, Ryan | U.S. House | CT | Republican | 1 |
| Meek, Scott Allen | President | US | Independent | 2 |
| Meeks, Gregory W. | U.S. House | NY | Democratic | 2 |
| Meeks Milojevich, Janai | U.S. House | CA | Democratic | 2 |
| Meeks, Timothy R. Mr. | President | US | Independent | 1 |
| Mehta, Leslie | U.S. House | VA | Democratic | 1 |
| Mehta, Rik | U.S. House | NJ | Republican | 1 |
| Mehta, Rikin | U.S. Senate | NJ | Republican | 1 |
| Mehta, Urvishkumar Mr | U.S. Senate | CA | FED | 1 |
| Meier, Rhett Wilkinson Mr. | President | US | Green | 1 |
| Meijer, Peter Mr. | U.S. House | MI | Republican | 1 |
| Meijer, Peter Mr. | U.S. Senate | MI | Republican | 1 |
| Meiring, Eric Richard Rev | President | US | Independent | 1 |
| Meiring, Eric Richard Reverend | U.S. Senate | OH | Independent | 1 |
| Meissner, Stuart | U.S. Senate | NJ | Republican | 1 |
| Mejia, Kenneth | U.S. House | CA | Green | 1 |
| Mejias, Eduardo | U.S. House | FL | Republican | 1 |
| Mele, Gregg | U.S. House | NJ | Republican | 1 |