The Dow rose 38 points, or 0.3 percent, to 14,334 as of 9:52 a.m. Eastern. The Standard & Poor's 500 gained two points, or 0.1 percent, to 1,543. The Nasdaq composite advanced three points to 3,225.
The market got a boost after the Labor Department reported that the number of Americans seeking unemployment aid fell by 7,000 last week, driving the four-week average to its lowest in five years. The drop is a positive sign ahead of Friday's employment report.
The Dow barreled through a record high Tuesday and added to those gains Wednesday. The index is on track for its fifth straight gain.
Investors have been buying stocks on optimism that employers are slowly starting to hire again and that the housing market is recovering. Growing company earnings are also encouraging investors to get into the market.
The Dow is 9.4 percent higher this year and the broader S&P 500 is up 8.2 percent.
The yield on the 10-year Treasury note rose four to 1.98 percent from 1.94 percent.
Among stocks making big moves:
— PetSmart fell $4.67 to $61.88 after the company reported its fiscal fourth-quarter earnings. Profits for the pet store chain rose but its forecast for this year disappointed investors.
— Pier 1 Imports fell 91 cents to $22.36 after the home decor company issued an earnings forecast that was below Wall Street analysts' estimates.
— Supermarket chain Kroger rose $1.14 to $3.59 after the company's fourth quarter profit handily beat Wall Street expectations.