* S&P, Dow set for four weeks of gains in a row
* Oracle dips after bleak forecast for cloud business
* Futures up: Dow 94 pts, S&P 500 8.75 pts, Nasdaq 20.5 pts (Adds comment, details on companies; updates prices)
By Rama Venkat Raman
Dec 15 (Reuters) - Wall Street was set to open higher on Friday, recovering from a bout of uncertainty surrounding the passage of the Republicans' much-awaited tax overhaul bill.
The S&P 500 fell the most in a month on Thursday after Republican Senators Marco Rubio and Mike Lee declined to back the bill without changes to child tax credits.
"What Rubio was looking for is more help for the lower-income people, child tax credits. That's something that can easily be adjusted, so the bill will move forward," said Andre Bakhos, managing director at Janlyn Capital.
"Things are looking like this (tax bill) will get through. But the market is going to be sensitive to any inkling that it's going to be a problem."
Stocks have rallied this year, partly on hopes of corporate tax cuts that U.S. President Donald Trump promised during his election campaign last year. The bill, in its current form, proposes a corporate tax cut to 21 percent from 35 percent.
The stock markets are expected to see a rise in trading volume as the session progresses with traders likely to close hedging positions of futures, options and stocks or roll them over at the last minute.
At 8:28 a.m. ET (1328 GMT), Dow e-minis were up 94 points, or 0.38 percent, with 1,808 contracts changing hands.
S&P 500 e-minis were up 8.75 points, or 0.33 percent, with 22,818 contracts traded.
Nasdaq 100 e-minis were up 20.5 points, or 0.32 percent, on volume of 2,679 contracts.
The S&P 500 and the Dow were on track to record four weeks of gains in a row, while the Nasdaq was set to post its first rise in three weeks.
Bitcoin rose to an all-time high of $17,751 on Bitstamp exchange in the day, boosting related stocks, including Riot Blockchain, Overstock.com, Xunlei by 1 percent to 11 percent in early premarket trading.
Oracle's shares slipped 6.85 percent after the company's forecast for the current-quarter cloud revenue growth missed estimates and the second quarter sales in the business disappointed.
CSX Corp fell over 12 percent and was the most traded stock on all U.S. exchanges premarket after the No.3 U.S. railroad said its Chief Executive Hunter Harrison was taking medical leave, a decision that comes in the middle of a controversial turnaround plan.
Costco Wholesale shares rose about 3 percent after the retailer's quarterly profit and revenue beat analysts' estimates.
Reporting by Rama Venkat Raman in Bengaluru; Editing by Arun Koyyur