Sen. John McCain (R-Ariz.) said Sunday that Rep. Todd Akin's (R-Mo.) recent controversial comments about rape and pregancy are problematic for the GOP, and that the congressman "would not be welcome by Republicans in the United States Senate."

"It's a problem. There is no doubt about that," McCain said on NBC's "Meet The Press," when asked about the impact of Akin's remarks on the Republican presidential ticket. "Mr. Akin should recognize having the nomination of your party is a privilege and if you abuse that then you are not eligible to keep it. What he said was unacceptable."

Akin stoked widespread controversy when he said in an interview broadcast last weekend that "legitimate rape" rarely causes pregnancy. Republicans across the country have called for Akin to end his campaign. But the congressman has vowed to stay in the race.

Republican National Committee Chairman Reince Priebus said on CNN's "State Of The Union" that Akin's refusal to end his Senate run could imperil Republicans' chances of taking over the Senate majority in November.

"I think it makes it more difficult," said Priebus, who echoed other Republicans' calls for Akin to drop his bid.

McCain said he was surprised that the Republican presidential ticket was running so close with the Democratic ticket, given the setbacks the party has recently experienced, but is encouraged about its odds moving forward.

"I'm surprised that we -- the Romney/Ryan ticket -- are neck-and-neck in the polls right now, particularly given a couple of the setbacks we have experienced, which means to me this attack strategy of Obama not being able to defend his record is wearing a little thin with the American people."

McCain also expressed his hope that the Republican National Convention, which has been delayed over concerns about Tropical Storm Issac, would resume Tuesday. "It's Wednesday and Thursday that are the big moments," he added.

Updated at 12:06 p.m.