McCain seeking strong Potomac results to line up GOP

WASHINGTON (CNN) -- As the Democratic race heats up in Tuesday's so-called Potomac primaries in Maryland, Virginia and the District of Columbia, Sen. John McCain is hoping for big wins to help reassure the GOP base he is the party's inevitable candidate.

For McCain, the emphasis seems to be holding strong and trying to win over conservatives -- and voters in the remaining contests.

On Monday, he won endorsements from former Florida Gov. Jeb Bush and evangelical leader Gary Bauer.

Over the weekend at the Conservative Political Action Committee conference in Washington, McCain appeared with former Virginia Sen. George Allen, and he previously received the support of former Virginia Gov. Jim Gilmore, two influential Republicans in the commonwealth.

Still, McCain could use a strong showing in the Potomac primaries, especially after losing in Louisiana and Kansas to former Arkansas Gov. Mike Huckabee over the weekend.

At stake Tuesday: 113 GOP delegates.

McCain won Washington state by a narrow margin -- something Huckabee has challenged.

When asked by CNN about his chances Tuesday, McCain said they were good and he is "guardedly optimistic as always." Watch the full interview here »

On Monday, though, McCain was more optimistic, saying he had "great confidence that we will [win]." Watch as McCain campaigns in Virginia »

Virginia could be a crucial win for the Arizona senator, a state where independents -- a group McCain does well with -- are able to vote.

"We are doing fine. We have 700 and some, close to 800 delegates and the last time I checked, Gov. Huckabee has very few, so I think I am pretty happy with the situation we are in," McCain said.

But McCain's losses are a signal some conservatives are not happy with him. Huckabee, meanwhile, hopes that uneasiness continues in Virginia. Watch Huckabee campaign ahead of the Potomac primaries »

"I think our victories in Kansas and in Louisiana have show them that this race is not over," Huckabee said.

Huckabee says he's staying in the race and that conservatives need a choice.

McCain is hoping for a strong showing Tuesday and hoping to not repeat last weekend's results, despite the fact that it's virtually impossible for Huckabee to catch up to McCain when it comes to the delegate estimate.

So far, McCain has 723 delegates to Huckabee's 217. A win in all three states for McCain could put him closer to the magic number of delegates -- 1,191 -- needed to win the party's nomination. E-mail to a friend

CNN's Mary Snow and Dana Bash contributed to this report.

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