The difference likely results from some of the taxable income on Form 1040 line 10 being taxable at the 15% long-term capital gains rate rather than as ordinary income at the 24% ordinary tax rate. Only the portion of line 10 that is not taxed as long-term capital gains is taxed at the ordinary income tax rate on the Tax Computation Worksheet.
TurboTax's result suggests that $22,920 of the $238,426 it taxed at the 15% long-term capital gains rate and only the remaining $215,506 is taxed as calculated on the Tax Computation Worksheet:
15% * $22,920 + 24% * ($238,426 - $22,920) - $11,421 = $43,738
If this is the case, on the Qualified Dividends and Capital Gain Tax Worksheet you should see $22,920 on line 19 and $215,506 on line 7.
