Fresno Democrat Jim Costa and Hanford Republican David Valadao are proving the pundits right as both appear headed to victory in their respective congressional races.

Costa declared victory around 11:30 p.m. over Fresno Republican Brian Whelan in the newly drawn 16th Congressional District, and Valadao is well ahead of Fresno Democrat John Hernandez in his quest to win a first term in the 21st District.

With with 78% of precincts reporting in the 16th District, Costa had 54.4% of the vote to Whelan's 45.6%; and with 45% of precincts reporting in the 21st District, Valadao had 61% to Hernandez's 39%.

"Hopefully this election will mark a change in which my Republican colleagues, along with my Democratic colleagues, figure out that we need to work together," Costa said.

He said he hoped to reach 60% of the vote.

Earlier in the evening, Whelan was conceding nothing: "We are optimistic about being successful in this great election."

Valadao was equally excited about the prospects of moving to Congress after a single term in the state Assembly.

"I'm thrilled," he said. "I couldn't be happier. I'm looking forward to doing something for my district."

At 12:20 a.m., however, Hernandez wasn't conceding as he waited for more returns from Kern County, which has traditionally been strongly Democratic.

"We're watching the polls," he said. "It's not quite over yet. We'll see what's going to happen here."

Both races had, to varying degrees, been on the radar screens of political watchers both locally and in Washington D.C.

Costa was there early because of his narrow 2010 win over Hanford cherry farmer Andy Vidak. Republicans had insisted he was vulnerable.

But that was in the old 20th Congressional District, which ran from central Fresno south to Bakerfield and included parts of Kern and all of Kings County. Costa's new 16th District includes heavily Democratic parts of Fresno, as well as the western half of Madera County and all of Merced County.

In addition to the new district -- which has a 15-percentage-point Democratic voter registration advantage -- Costa was also able to mend fences with some Republicans, especially in agriculture, who were angry at some of his votes.

Whelan's campaign also was never able to catch on with national Republicans. He made contender status with the National Republican Congressional Committee's "Young Guns" program, but was never able to reach the top rung, which brings with it campaign funds.

Because of that, the 16th District was no longer considered competitive as September moved to October.

The 21st District race, by contrast, was the exact opposite.

Valadao rolled to a comfortable primary victory, and Fresno City Council Member Blong Xiong, the choice of establishment Democrats, finished third. Hernandez finished second, earning him the right to challenge Valadao under the state's new top-two primary.

But Hernandez seemed to constantly struggle to gain traction. Fundraising was slow, and the campaign was consistently in debt.

As a result, most political watchers figured Valadao would cruise to victory, even though Democrats, as in the 16th District, hold a 15-percentage-point registration advantage.

But in early October, an article in the National Journal -- a nonpartisan magazine that covers national politics and policy -- quoted a Republican saying private polling was moving "the wrong way" for Valadao.

A short time later, a group known as Crossroads Grassroots Policy Strategies announced it had put together a television ad attacking Hernandez and said it was spending more than $600,000 on the race.

The Crossroads GPS ad buy caught the attention of everyone, and suddenly the 21st District was in play. Hernandez fanned the flames by saying an internal poll showed him in striking distance.

Other Valley Congressional races

4th Congressional District: Rep. Tom McClintock, R-Elk Grove, was soundly beating Democrat Jack Uppal by a margin of 61.4% to 38.6%, with about 80% of the precincts reporting. The district covers the Sierra foothills as far south as Madera and Fresno counties.

22nd Congressional District: Incumbent Rep. Devin Nunes, R-Tulare, was leading challenger Otto Lee by a 64% to 36% margin. Lee, a Democrat, moved to Clovis in June from Sunnyvale.

23rd Congressional District: Rep. Kevin McCarthy, R-Bakersfield, had a nearly 3-1 lead over challenger Terry Phillips in the district, which covers Kern and portions of Tulare counties. Phillips described himself as an independent.