Democratic presidential candidate Bernie Sanders defeated front-runner Hillary Clinton in caucuses in three Western states—Washington, Alaska and Hawaii—on Saturday, boosting his campaign as the race moves to the more liberal northeastern states, including Clinton's home state of New York, where the senator from Vermont expects even better results.

Although Sanders' victories barely dented Clinton's significant delegate lead, they exposed the former State Secretary's weaknesses, particularly with young voters and liberal activists who have been drawn by Sanders' liberal message, the Associated Press reported.

Sanders gained 55 new delegates from Washington, Alaska and Hawaii, raising his total delegate count to 1,004. Clinton picked up 20 new delegates from the three states to pad her total delegate count to 1,712, according to the latest tally by Real Clear Politics.

Clinton needs just 670 more delegates to clinch the Democratic nomination. Sanders still trails Clinton by 708 delegates.

In an interview with The Associated Press, Sanders said he expects to close the delegate gap with Clinton in the state contests ahead.

"The Deep South is a very conservative part of the country," he said. "Now that we're heading into a progressive part of the country, we expect to do much better."

Clinton barely campaigned in Washington, Alaska and Hawaii, apparently conceding defeat to Sanders in those three states.

Her eyes are set though on the April 19 contest in New York, where she seeks to win a large share of the delegates at stake and avoid an upset loss to Sanders in a state she represented in the Senate.

Meanwhile, two new polls show Texas Sen. Ted Cruz narrowly leading Donald Trump in Wisconsin, a state that will hold its winner-take-all primary on April 5, with 42 delegates at stake, Newsmax reported.

Trump already has 739 delegates and needs 498 more to reach the 1,237-delegate threshold needed to clinch the Republican presidential nomination. Cruz has 465 delegates, still trailing Trump by 274, according to Real Clear Politics.

Before Wisconsin, North Dakota will hold its caucus on April 1 with 28 delegates at stake.

Then on April 19, New York New will hold its primary with 95 delegates up for grabs on proportional allocation basis.

In a statewide Emerson College Polling Society survey conducted from March 20-22 of 439 likely GOP primary voters in Wisconsin, with a margin of error of plus or minus 4.6 points, Cruz has 36 percent voters' support to Trump's 35 percent. Ohio Gov. John Kasich has 19 percent.

In a Basswood Research survey conducted for The Washington Free Beacon of 500 likely Republican primary voters, conducted on March 19 and 20, Cruz has 36 percent to Trump's 31 percent and Kasich's 21 percent.

Wisconsin is expected to be a crucial contest in the race for the Republican nomination as Trump looks to expand his lead while Cruz clings to his fading hopes of overtaking him as the front-runner ahead of a potential contested Republican convention.