Democratic presidential candidate Hillary Clinton targeted small groups of voters in Maryland and Virginia while rival Barack Obama held large-scale rallies as he tries to cement another primary sweep tomorrow.

Clinton, 60, a New York senator, began her day addressing several dozen supporters at the National Council of Negro Women in Washington before visiting a General Motors Corp. plant building hybrid transmissions in Maryland. Later today, she plans to deliver a guest lecture at the University of Virginia.

Obama, 46, an Illinois senator, is leading in polls in Virginia, Maryland and Washington, D.C., which all vote tomorrow. Clinton argued that she is the best candidate to take on Republican John McCain in the November general election.

McCain "will run a very aggressive and vigorous campaign, and we have to start imagining right now what it will take for our nominee'' to beat him, Clinton said this morning. "I feel totally comfortable standing up there with John McCain.''

Obama held his first rally today at the Comcast Center arena at the University of Maryland's College Park campus. The arena, which seats more than 17,500 people, was packed with cheering Obama supporters. He plans a similar event at a stadium in Baltimore.

At stake tomorrow are 168 pledged delegates to the Democratic National Convention in August from the two states and Washington, D.C. At least 2,025 delegates are needed to win the Democratic presidential nomination, and the two candidates are in a neck-and-neck race that may last into June.

Weekend Contests

Obama bested Clinton in four states over the weekend, winning caucuses in Maine yesterday 60 percent to 40 percent and rolling up similar margins in caucuses in Nebraska and Washington along with the primary in Louisiana.

February is likely to be a tough month for the Clinton campaign, with Obama favored in the Feb. 19 contest in Hawaii and the primary in Wisconsin. The former first lady is seeking to recoup some momentum in Ohio, Texas and Pennsylvania over the next two months.

"I'm winning delegates, he's winning delegates; we're just going to keep moving forward,'' Clinton told reporters today.

Clinton yesterday replaced her campaign chief Patti Solis Doyle, who has run her campaign since January 2007, with longtime adviser Maggie Williams.

"When a campaign changes managers at a crucial moment as the finish line is within view, it means there is something not right,'' said Steffen Schmidt, a professor of political science at Iowa State University.

'Very Long Campaign'

Clinton and her campaign officials denied that Doyle was forced out.

"This was Patti's decision,'' Clinton said today in White Marsh, Maryland. "This has already been a very long campaign. It takes quite a toll.''

Both Clinton and Obama are courting the endorsement of former presidential candidate John Edwards. Clinton met with Edwards on Feb. 7 at his home in Chapel Hill, North Carolina, Clinton spokesman Mo Elleithee said. He declined to comment further about the meeting, saying it was a private conversation.

Obama said he planned to meet with the former North Carolina senator, as well.

"It will be rescheduled, we're going to make it happen,'' Obama said today as he campaigned in Silver Spring, Maryland.

Delegate Race

Obama has 925 pledged delegates to Clinton's 896, according to an unofficial tally complied by thegreenpapers.com, a nonpartisan Web site that compiles election statistics

The count doesn't include the 796 so-called super delegates, Democratic Party officials and officeholders who aren't bound by primary or caucus results and can back whomever they choose.

McCain, 71, has a clearer path to the Republican nomination and he returned to campaigning today after taking most of the weekend off. McCain's drive was slowed over the weekend by losses to former Arkansas Governor Mike Huckabee in Kansas and Louisiana.

The Arizona senator, at a news conference today in Annapolis, Maryland, played down the two losses and the narrow win he pulled out in Washington.

"We're doing fine,'' he said.

Endorsements

He was endorsed today by former Florida Governor Jeb Bush, the brother of President George W. Bush, who called him a "devoted conservative leader.''

McCain has been confronted by skepticism from some leaders of conservative groups and has tried to win their support with endorsement's and assurances.

The president, while not explicitly endorsing McCain, yesterday called McCain a "true conservative' and vowed to help him win election if he wins the nomination.

McCain today also picked up endorsements from Gary Bauer, who was an adviser in President Ronald Reagan's administration and is a former head of the Family Research Council, a Washington-based advocacy group, and Texas Representative Jeb Hensarling. Hensarling is chairman of the Republican Study Committee, which works to shape conservative policy for the House, where McCain once served.

By Kristin Jensen and Indira Lakshmanan, Bloomberg, February 11, 2008