1) Two different politicians have run for office from jail: Eugene V. Debs ran for president in 2020 and got 1 million votes in jail. Lyndon LaRouche ran for Congress in 1990 in Virginia, got 26,000 votes.
2) If indicted, but not tried or convicted, there is nothing to stop someone from running and winning. Should Trump win in 2024, he could immediately pardon himself from all fed charges. He would still be subject to NY charges by Bragg, if they were still around.
3) Should a NY state jury convict, nothing could happen to Trump until 2029 when he left office, for there is no provision in the constitution that a president can be removed except by the House impeaching and the Senate convicting.
4) Clinton’s CIVIL case from Paula Jones was ruled as legitimate because it had nothing to do with removing him from office. The impeachment came when it was discovered by Ken Starr that Clinton had lied in federal testimony ABOUT the Jones case.
Trump actually likely could pardon himself on the state charges, too. The idea he could not is just a more mainstream media spin. (I’ve read and heard many real lawyers address this point.)