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* TSMC results power semiconductor stocks

* Delta Air Lines CEO calls 2021 year of recovery

* Weekly jobless claims rise more than expected

* Biden to outline stimulus plan on Thursday evening

* Indexes up: Dow 0.25%, S&P 0.13%, Nasdaq 0.29%

NEW YORK, Jan 14 (Reuters) - Wall Street gained ground on Thursday, with the Dow and Nasdaq briefly touching record highs, as investors' hopes for fresh fiscal stimulus ahead of President-elect Joe Biden's pandemic aid proposal were countered by weakening labor market conditions.

The Labor Department's weekly jobless report showed the number of Americans filing first-time claims for unemployment benefits increased more than expected last week, underscoring the impact of a resurgence in COVID-19 infections.

However, the S&P 500 rose for the seventh time in nine sessions as investors counted on Biden unveiling on Thursday evening a stimulus plan that could exceed $1.5 trillion.

"There's a tug-of-war going on between the prospects for further fiscal stimulus, as a result of Democratic control of the Senate, and a jobs market that has a long way to go before it heals," said Emily Roland, co-chief investment strategist at John Hancock Investment Management. "You have these competing forces going on which are keeping markets range bound."

But Roland noted that disappointing jobs data could provide "further fodder for Biden to potentially market this plan."

"Everybody's waiting to hear the details ... Whether it's $1 trillion or $2 trillion, that's a massive amount of fiscal stimulus," she said.

Investors also seemed reassured after U.S. Federal Reserve Chair Jerome Powell said an interest rate hike would not be coming anytime time soon and pushed back against suggestions that it might taper bond purchases any time soon.

By 2:12 p.m. ET (1912 GMT), the Dow Jones Industrial Average rose 77.52 points, or 0.25%, to 31,137.99, the S&P 500 gained 4.95 points, or 0.13%, to 3,814.79 and the Nasdaq Composite added 37.77 points, or 0.29%, to 13,166.72.

Six of the 11 major S&P sectors rose with economically-sensitive energy showing the biggest percentage gains.

The domestically-focused small-cap Russell 2000, as well as the Dow Jones Transports index, considered a barometer of economic health, both scaled all-time highs.

Helping the transport index was a 3.9% gain in Delta Air Lines after Chief Executive Ed Bastian forecast 2021 to be "the year of recovery" after the coronavirus pandemic prompted its first annual loss in 11 years.

The S&P 1500 airlines index added 4%.

President Donald Trump became the first president in U.S. history to be impeached twice when the House voted 232-197 on Wednesday to charge him with inciting riots at the Capitol. The impeachment proceedings threaten to hang over the beginning of Biden's term.

While some investors worry about the impact impeachment proceedings could on the stimulus boost, Max Gokhman, head of asset allocation at Pacific Life Fund Advisors in Newport Beach, California played down these fears.

"I don't think the delay (in fiscal aid) of a few weeks due to impeachment trial is necessarily going to derail the further economic boost that we're going to get from the stimulus," he said.

The Philadelphia semiconductor index was up 2.9% and hit a record high with a big boost Taiwan Semiconductor Manufacturing Co Ltd. The chip manufacturer's US shares were up 9% after it announced its best-ever quarterly profit and raised revenue and capital spending estimates.

Investors were also waiting for the earnings season to kick into full swing with results from JPMorgan, Citigroup and Wells Fargo slated for Friday.

First-quarter and 2021 corporate guidance will be key for investors as new lockdowns threaten to push back a recovery in corporate earnings, according to investment banks.

Advancing issues outnumbered declining ones on the NYSE by a 2.99-to-1 ratio; on Nasdaq, a 2.86-to-1 ratio favored advancers.

The S&P 500 posted 45 new 52-week highs and no new lows; the Nasdaq Composite recorded 325 new highs and three new lows.

(Additional reporting by Devik Jain and Medha Singh in Bengaluru; Editing by Marguerita Choy)