* Trump Jr email chain cites Russian support for his father
* Yellen could shed light on pace of monetary tightening
* Snap shares drop after downgrade from underwriter Morgan Stanley
* Indexes: Dow up 0.04 pct, S&P down 0.1 pct, Nasdaq up 0.2 pct (Updates to late afternoon)
By Caroline Valetkevitch
July 11 (Reuters) - The Dow and Nasdaq were higher in late afternoon trading on Tuesday, reversing earlier losses as the Senate's announced delay to its August break gave some relief to investors worried about the progress of the Republican agenda.
U.S. Senate Republican leader Mitch McConnell announced a two-week delay in the Senate's August recess to provide more time to work on legislation and approve nominees.
"It says to me there's a commitment to make some of the changes that the markets would like to see," Brad McMillan, chief investment officer for Commonwealth Financial in Waltham, Massachusetts.
The S&P 500 was still down slightly, but well off its low of the day, which followed the release of an email chain from President Donald Trump's eldest son.
The emails referred to a top Russian government prosecutor offering the Republican Trump campaign damaging information about Democratic rival Hillary Clinton.
"There was a knee-jerk reaction to the Trump Jr emails, but it's a not a problem today, so the reaction was overstated," McMillan said. Uncertainty over whether the Trump administration would be able to push through its agenda this year have weighed on the market, especially after repeated delays in getting a new health care bill passed.
The Dow Jones Industrial Average was up 8.32 points, or 0.04 percent, to 21,416.84, the S&P 500 had lost 2.52 points, or 0.10 percent, to 2,424.91 and the Nasdaq Composite had added 10.83 points, or 0.18 percent, to 6,187.22.
Energy led gains, with a 0.6 percent increase.
Upcoming congressional testimony from Federal Reserve Chair Janet Yellen could shed more light on the pace of U.S. monetary tightening. Yellen will deliver her semi-annual monetary policy testimony before the House Financial Services Committee on Wednesday.
Snap Inc shares fell 8.1 percent, after lead underwriter Morgan Stanley downgraded the stock and raised concerns about the social media company's ability to compete against rival Instagram.
Advancing issues outnumbered declining ones on the NYSE by a 1.05-to-1 ratio; on Nasdaq, a 1.11-to-1 ratio favored advancers.
The S&P 500 posted 27 new 52-week highs and 11 new lows; the Nasdaq Composite recorded 81 new highs and 69 new lows. (Additional reporting by Ankur Banerjee and Anya George Tharakan in Bengaluru; Editing by Arun Koyyur and Nick Zieminski)