DELAWARE, Ohio (AP) — Donald Trump is saying he won't commit to honoring the results of November's election because he wants to reserve his right to file a legal challenge "in the case of a questionable result."

Trump, speaking in Ohio on Thursday, said "of course I would accept a clear election result." But he stressed that he was not sure he would receive one, citing misleading statistics on voter fraud. He alleged without evidence that Hillary Clinton's campaign was trying to "rig" the election.

Trump made the unprecedented assertion during the final presidential debate Wednesday. Asked if he would concede if he loses the election, Trump said, "I will look at it at the time."

He opened his rally in Delaware, Ohio by joking that he would honor the result "if I win."

McCain affirms need to accept election results

WASHINGTON (AP) — Republican Sen. John McCain, who lost the 2008 presidential election to Barack Obama, says he conceded defeat "without reluctance" even though he didn't like the outcome.

McCain said in a statement that he doesn't know who will win this presidential election. But he says the loser has always congratulated the winner and called him "my president."

McCain said, "That's not just the Republican way or the Democratic way. It's the American way. This election must not be any different."

McCain did not mention Donald Trump by name in his statement Thursday following the Republican nominee's refusal to say whether he will accept the election result.

McCain withdrew his tepid endorsement of Trump after a video surfaced of Trump bragging about groping women.

Meanwhile, the No. 3 Senate Republican is criticizing Donald Trump for refusing to say he'll accept the results of next month's election.

John Thune of South Dakota said in a statement Thursday that America's electoral process is "the cornerstone of our democracy" and that "suggesting otherwise undermines an electoral system that is a model for nations around the world."

Thune did not mention Trump by name. At Wednesday's debate, the Republican presidential nominee refused to commit to accepting election results, citing unsubstantiated concerns about massive voter fraud.

Thune has wavered in support of Trump. He had said Trump should withdraw from the race after a video surfaced of Trump crudely talking about grabbing women. But Thune later said he would still vote for Trump.

Meanwhile, U.S. Attorney General Loretta E. Lynch has expressed confidence in the American election system, saying she doesn't see a threat to the integrity of the outcome.

Lynch spoke in Rome on Thursday, the day after Donald Trump refused to say whether he would honor the results of the election should he lose.

She told reporters that all 50 states have tools in place to protect voting systems "from attacks and hacks and the like." She added that it would be very difficult for "any outside actor to try to actually impact or alter election results."

Lynch says officials would investigate allegations of interference, but "at this point I don't think that it is helpful to speculate about what has not occurred, and we don't see as an actual threat."

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